Magnetic belt recorder



Feb. 3, 1970 R. K. WALKER $493,231

MAGNETIC BELTHBECORDER Filed Nov. 15. 1968 F' C5. I +3 2 Sheets-Sheet lINVENTOR RICHARD K- WALKER I BY ov-7A AGENT b- 1970 R. K. WALKERMAGNETIC BELTjRECO RDER F il ed Nov. 15, 1968 III. 7 r H 2. on w v q N\I .i-IIIIIIIIIIIIIIIIIIIII! 2 m l a IIIIIIIIIIIII'III I I I I I I I I Il I l I I I I I I I I i I I I I I I I N I l 0' L INVENTOR RICHARD K.WALKER AGENT United States Patent 3,493,231 MAGNETIC BELT RECORDERRichard K. Walker, Convent, N.J., assignor to McGraw- Edison Company,Elgin, 111., a corporation of Delaware Filed Nov. 13, 1968, Ser. No.775,442 Int. Cl. Gllb /02 US. Cl. 274-4 8 Claims ABSTRACT OF THEDISCLOSURE An object of the invention is to provide a small compactmagnetic belt recorder adapted to serve as a portable pocket-sizemachine for recording dictation.

Another object is to provide such machine with a drive and beltsupporting mechanism of novel design permitting easy loading andunloading of the belt record.

Another object is to provide such drive and supporting mechanism whichis shiftable between running and loading conditions as the case isclosed and opened.

A still further object is to provide such machine of a simple andeconomical design and construction.

In the description of my invention reference is had to the accompanyingdrawings, of which:

FIGURE 1 is a bottom plan view of the drive mechanism for a magneticbelt recorder according to the invention, as seen from the line 1-1 ofFIGURE 2;

FIGURE 2 is a right hand view of this belt recorder showing the caseclosed and partly broken away and showing the belt supporting mechanismin its running condition;

FIGURE 3 is a left hand sectional view taken on the line 3-3 of FIGURE 1showing the case in open condition and the belt supporting mechanism inloading condition; and

FIGURE 4 is a fractional view taken on the line 4-4 of FIGURE 3 showinga detail of the belt drive mechamsm.

The present portable belt recorder has a rectangular case comprising anupper housing section and a lower closure section 11. The housingsection is of an inverted pan shape with an open back wall and theclosure section is of an upright pan shape with an upstanding back wallhinged at 12 to the housing section so that the two sections can swingapart from a break line 13 at the sides fractionally shown in FIGURES 2and 3. The upper case section has suitable controls at the top and sideswhich need not be herein described for purposes of the presentinvention. Mounted in this upper case section is a framework 14comprising a lower shallow casting with left and right sidewalls 15 and16 joined by front and back crossbars 17 and 18, and a deeper uppercasting with a left wall 19 (FIGURE 3) secured to the lower wall 15 asby screws not shown and a right wall 20' above the lower casting (FIGURE2) joined to the left wall 19 by upper and lower walls 21a and 21b and arear wall 22. In this construction the two castings are supported incantilever fashion from their joined left walls leaving a space Stherebetween for receiving the upper run of a belt record 23 as is latermore fully described.

Mounted at the front left hand portion of the machine is a motor 24having a drive shaft 25 coupled by a belt 26 to a flywheel 27 at therear left portion of the machine. The flywheel is mounted on a shaft 28journaled in the frame wall 19 and extending to the right thereofthroughout the distance between the side walls 19 and 20. On the portionof the shaft 28 between the sidewalls is mounted a sleeve 29 as ofsuitable plastic to form a drive roller for engaging and propelling themagnetic belt record 23.

Coupled by a train of gears 30 to a pinion 31 on the shaft 28 is a feedscrew 32 journaled at its ends in the sidewalls 19 and 20. Also spanningthese sidewalls is a support rod 33. Mounted slidably on the support rod33 is a U-shaped carriage 34 (as viewed from the top) having a roller 35journaled on a stud 36 staked to the backwall thereof and riding in across slot. 37 in the frame wall 22. The carriage is thus supported fortraveling movement crosswise of the upper run of the belt record 23.Mounted in the carriage 34 is a magnetic recorder-reproducer head 38having pole pieces 39 at its lower end for engaging the belt record.Pivoted at 40 between two upstanding cars 41 of the sidewalls of thecarriage 34 is a rocker 42 carrying a feed nut 43 at its forward end forengaging the feed screw 32 responsive to a biasing of the rocker by aspring 44 between the rocker and the carriage, Secured to the rear endof the rocker is a push button 45 upstanding through a slot 46 in a topwall of the case. By pressing downwardly on this button the feed nut 43can be disengaged from the feed screw 32 to permit the carriage to beshifted manually crosswise of the belt record. When the feed nut isengaged and the motor is running the head 38 is driven gradually acrossthe belt record in synchronism with the revolving movement thereof todescribe a track of successive convolutions of equal pitch on the beltrecord.

The lower casting above-described carries the magnetic belt supportingmechanism. This supporting mechanism comprises a front take-up roller48, a back idler roller 49 and a guide roller 50. The take-up roller 48is journaled between the side arms 51 of a yoke 52 se cured at itscenter by a vertical pivot 53 to a plunger 54. The plunger is slidablymounted from the front of the machine in a horizontal aperture 55provided in a central block-shaped portion 17a of the crossbar 17. Theplunger is backed by a compression spring 56 to urge the take-up rollerforwardly while allowing the roller to tilt sidewise about the centralvertical pivot 53. The idler roller 49 is journaled on a fixed axisbetween the side plates 15 and 16. The guide roller 50 is journaled on ashaft 58 secured rigidly at its ends in left and right levers 59 and 60both of which are pivoted on a common axis. For example, the left lever59 is pivoted on a stud 61 in the side plate 15 (FIGURE 3) and the rightlever 60 is secured to a stub shaft 62 journaled in the end plate 16(FIGURE 2). The two levers may be further rigidly interconnected by across rod 63 so that when the left lever 59 is turned it will swing theguide roller in parallel with the idler roller 49. Such turning movementof the lever 59 is effected as the closure 11 is opened and closed as bya link 63 pivoted at one end to a bracket 64 on the inner wall of theclosure 11 and pivoted at its other end to an arm 59a of the lever 59extending rearwardly past the pivot stud 61. Thus, when the closure isopen the guide roller 50 is in a lower backward position about in linewith the take-up roller 48 and idler roller 49 as shown in FIGURE 3, butas the closure is swung to closed position the guide roller 50 is swungupwardly past the back side of the drive roller 29 into the positionshown in FIGURE 2.

When the guide roller 50 is in its lower position the belt supportingmechanism is in a collapsed condition allowing the belt record 23 to beinserted from the right side of the machine into a position looselyenveloping 3 the rollers 48, 49 and 50 and the lower casting with theupper run of the belt passing through the space S between the lower andupper castings (FIGURE 3). As the closure 11 is swung to closed positionthe guide roller 59 is swung to its upper position causing the up perrun of the belt to be wrapped around the back side of the drive roller29. Also, in this upward movement of the guide roller the span aroundthe rollers 48, 49 and 50 via the back side of the drive roller 29 islengthened causing the belt record to be tensioned around the driveroller with suitable retraction of the take-up roller 48 against theaction of the compression spring 56.

Within the lower casting structure is a platen 65 pivoted at its forwardend on a cross rod 66 secured at its ends in the side plates and 16.This platen extends forwardly past the recorder head 38 and has thereona pressure pad 67 as of soft felt movable through an opening 68 in thetop wall of the lower casting. When the platen is in a free condition itis urged upwardly by a pair of torsion springs 69 on the cross rod 66(FIGURE 1) to move the pressure pad 67 against the underside of theupper run of the belt record 23 and hold it thus in engagement with thepole pieces 39 of the recorder head.

At the outer side of the right end plate 16 of the lower casting is alever 70 pivoted at its forward end on a stud 71 in the end plate 16.This lever has an in wardly bent lug 72 extending through an opening 73in the end plate 16, which overlies the right edge of the platen 65intermediately thereof. When the closure 11 is in closed position thelever 70 is unrestricted with the result that the spring 69 then movesthe pressure pad 67 upwardly to engage the upper end of the belt withthe recorder head. However, as the closure 11 is opened a cam 74 on thestud 62 turns downwardly against the lever 70 to shift the platen 65into a lower position to disengage the pressure pad 67 from the recorderhead.

On the central rearward portion of the platen 65 is a rearwardlyextending lug 75 passing through a clearance hole 76 in the wall 18 andthrough a narrow coupling hole 77 in a crossbar 78 (FIGURE 4). Thecrossbar 78 is slidably mounted for vertical movement by two studs 79 inthe back wall 18 passing with clearance through respective slots 80 inthe crossbar. This crossbar has two pairs of lugs 81 struck forwardlytherefrom each of which carries a shaft 82 on which is journaled a pinchroller 83.

When the platen 61 is released for free upward movement the pinchrollers 83 are pressed against the drive roller by the springs 69 toprovide a firm driving engagement of the drive roller with the beltrecord. Since the pressure pad 67 is of a soft springy character itprovides sufiicient pressure of the belt record against the recorderhead without reducing substantially the pressure of the pinch rollers 83against the drive roller, When the closure 11 is opened the platen 65moves the crossbar 78 downwardly therewith away from the drive roller toclear a space between the pinch rollers and the drive roller to permitthe unloading and reloading of a belt record from and into the machine.

The embodiment of my invention herein particularly shown and describedis intended to be illustrative and not necessarily limitative of myinvention since the same is subject to changes and modifications withoutdeparture from the scope of my invention.

I claim:

1. In a dictating machine for recording on and reproducing from anendless flexible belt record: the combination of a frame, a guideroller, a take-uproller in spaced parallel relation to said guideroller, journal means on said frame at the ends of said take-up rollermounted for freedom of movement in directions towards and away from saidguide roller and biased away from said guide roller, said guide rollerhaving a loading position permitting a belt record to envelop looselysaid guide and take-up rollers, an idler roller journaled to said frameon a fixed axis within said belt record adjacent to the loading positionof said guide roller, a drive roller journaled to said frame on a fixedaxis for engaging the outer surface of said belt record adjacent to saidguide roller, and means for shifting said guide roller from said loadingposition to an operating position in parallel movement away from saididler roller and past said drive roller whereby to tauten the beltrecord around said rollers with one run of the belt being trainedpartially around said drive roller in driving engagement therewith.

2. The dictating machine set forth in claim 1 including means carriedwith said shifting means for pressing said belt record against saiddrive roller when said guide roller is in operating position.

3. The dictating machine set forth in claim 1 wherein said belt recordhas a magnetic coating, including a magnetic recording and reproducinghead for engaging said belt record to record on and reproduce therefrom,a pressure pad for holding the belt record in operative engagement withsaid head, and means on said shifting means for retracting said pressurepad from said head as said guide roller is returned to loading position.

4. The dictating machine set forth in claim 1 wherein said shiftingmeans comprises a lever pivoted to said frame on a fixed axis withinsaid belt record adjacent to said drive roller, including a journal onthe outer end of said lever for said guide roller.

5. The dictating machine set forth in claim 4 wherein said lever isL-shaped to clear said drive roller as said guide roller is shifted tosaid operating position.

6. The dictating machine set forth in claim 4 wherein said belt recordis provided with a magnetic coating on its outer surface, including amagnetic recorder-reproducer head for recording on and reproducing fromsaid belt record, a spring-pressed pad for pressing the belt recordagainst said head, and a roller carried by said lever intermediatelythereof for pressing the belt record against said drive roller when saidguide roller is in said operating position and for withdrawing said padfrom said head as said guide roller is shifted back to loading position.

7. The dictating machine set forth in claim 4, including a case havingtop and bottom sections hinged at one end for opening movement to exposethe outer ends of said rollers for a mounting and removal of a beltrecord, and means coupling said lever to said case for operating saidlever to shift said guide roller between said loading and operatingpositions as said case is opened and closed.

8. A support and drive mechanism for an endless flexible belt record,comprising a frame, an idler roller having a fixed journal in saidframe, a take-up roller spaced in a given plane from said idler rollerin parallel relation thereto, a journal for said take-up roller slidablymounted in said frame for movement in said given plane and spring urgedto bias said take-up roller away from said idler roller, a drive rolleroffset from a point on said given plane, a guide roller for drawing abelt record trained around said take-up and idler rollers in an Lconfiguration with the inner run of the belt record in partial wraparound relation with said drive roller and with the belt recordtensioned by said take-up roller, and means mounting said guide rollerfor swinging movement to a position beyond said idler roller from saidtake-up roller to enable the belt record to be trained during loadingaround said take-up, idler and guide rollers in a substantially flatconfiguration with said inner run of the belt record leading past saiddrive roller.

References Cited UNITED STATES PATENTS 3,416,806 12/1968 Springer et a1.274ll 3,372,938 3/1968 Hoag 2741l 2,273,916 2/1942 Westerkamp 27411LEONARD FORMAN, Primary Examiner R. A. FIELDS, Assistant Examiner

